Apparatus for purging refrigerating systems



Feb. 13, 1934. E. B. McCABE ,9 7,095

APPARATUS FOR PURGING REFRIGERATING SYSTEMS Filed Aug. 11. 1932 INVENTOR ATTORNEYS Patented Feb. 13, 1934 APPARATUS FOR PURGING REFRIGERATING SYSTEMS Edward B. McCabe, Carbondale, Pa, assignor to .Carbondale Machine Company,

Carbondale,

Pa., a corporation of Pennsylvania 'Application August 11, 1932. Serial No. 628,303

5 Claims. (Cl. 62-115) The invention relates to refrigerating systems inwhich a gaseous refrigerant such as ammonia is alternately liquefied and evaporated, and relates more particularly to means for purging the system of air and other foul gases which leak into the system or are formed therein, and which interfere with efficient operation.

In carrying out my invention, an auxiliary receiver is provided through which all of the liquid refrigerant is caused to pass, but in such a mannor that the main body of the liquid therein is substantially quiescent and with its upper level substantially below the top of the awnliary receiver. As the liquid refrigerant is permitted to lie in a substantially quiescent state in the auxiliary receiver, the refrigerant gas and the foul gases havea chance to separate, and the foul gas will separate from the refrigerant and collect in the space above the liquid. Thus the foul gases may be topped off or vented alittle at a time and with the minimum loss of refrigerant gas.

As an important feature of the present invention, the vent valve is automatically operated in a such a manner as to maintain a considerable quantity of gas and permit the escape of only a small percentage of such foul gases into the a mosphere, so that the purging operation does not continue suiliciently long to permit escape of refrigerant gas. This valve is automatically operated to open when the liquid in the auxiliary receiver reaches below a predetermined level, the valve being maintained open until the liquid has arisen again to this level.

In the accompanying drawing, there is shown 'for the purpose of illustration, one form of device embodying the present invention. In the drawing Fig. 1 is a perspective showing a portion of the refrigerating system embodying the present invention, and

Fig. 2 is a front elevation, partly in section, of the automatic air valve connected to the auxiliary receiver.

In Fig. 1 there is shown part of an ammonia refrigerating apparatus which, in the specific form shown, includes a plurality of condensers 10 of any suitable type, as for instance that shown and described in United States Patent No. 1,557,838. Each of these condensers is provided with the usual refrigerant gas inlet pipe 11 and a liquid outlet pipe 12. The outlet pipes 12 are controlled by valves 13, and lead into the top of a. main anhydrous receiver 14 to form a manifold therewith.

As an important feature of the present invention, there is provided an auxiliary receiver 15 having the lower portion thereof connected to the lower portion of the main receiver 14 by means of a pipe 16. Ainain deliver y pipe 17 leads from the lower portion of the auxiliary receive! 15, whereby all of the liquid refrigerant delivered by the main receiver passes to and through the auxiliary receiver on its way to evaporator.

the cooler or liquid and accumulate in the upp receiver. The auxiliary receiver 1 er part of the 5 may be provided with the usual gauge glass liquid level indicator 18 and has connected to of a gas outlet valve 19 through the top therewhich the air and other foul gases in said auxiliary receiver may be vented. This vent valve operated, but is advantageously of type shown in Fig. 2.

may be hand the automatic In the specific form shown in Fig. 2, the receiver 15 has an opening 21 in the top closed by a closure 20, having a passage 22 therethrough terminating at its inner end in a valve seat 23. Threaded in the outer side of the closure 20 is a valve casing 24 having a passage terminating at its outer end at an outlet 25 and controlled by a valve having a stem 26.

Within the receiver is a ball float 27 having a vertically extending valve stem 28 terminating in a needle valve for engaging the valve seat 23.

For vertically guiding the float,

there is provided a reticulated cage 29 supported by the closure 20.

This cage may have a spider 30 for guiding the valve stem 23. The valve stem 9 28 is preferably long enough so that the ball float 27 in its uppermost position is approximately midway of the height of the receiver.

In the operation of the apparatus, the liquid refrigerant is passed from the main receiver 14 10 to and through the auxiliary a manner that theliquid in the ceiver is stirred up or. agitated to receiver 15 in such auxiliary rethe minimum extent, and is maintained in substantially quiescent state. The air and other permitted to separate from the erant, and as they accumulate in foul gases are liquid refrigthe auxiliary receiver 15, the level of the liquid therein is forced down. When the auxiliary receiver 15 has become approximately half filled with gas, the no vent valve will open thereby permitting a small portion of the gas to be purged out. By this arrangement, the gas in the auxiliary receiver is never permitted to purge except a little at a time, and not to an extent sufficient to permit the escape of refrigerant gas. The valve 26 may be kept closed and manually opened from time to time. If the inner float controlled valve is open, gas may escape only until the liquid level rises to close it. The outlet is thus always spaced to a considerable distance above the surface of the liquid when gas can escape. The auxiliary receiver is shown of cylindrical form with liquid pipe connections at the bottom at one end, and the vent valve intermediate of the ends at the top. This receiver may be of various other shapes and may be mounted in a vertical position instead of a horizontal position.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:-

l. A refrigerating apparatus including a con denser, a main receiver for the liquefied refrigerant, an auxiliary receiver, a pipe connection between the lower part of said main receiver and the lower part of said auxiliary receiver for delivering all of the liquid refrigerant to said auxiliary receiver, a main liquid delivery conduit from the lower part of said auxiliary receiver, and a gas vent valve connected to the upper part of said auxiliary receiver.

2. A refrigerating apparatus including a main receiver for the liquefied refrigerant, an auxiliary receiver, a pipe connection from the lower part of said main receiver to the lower part of said auxiliary receiver for delivering all of the liquid refrigerant to said auxiliary receiver, a main liquid delivery conduit from the lower part of said auxiliary receiver, a vent valve at the upper part of said auxiliary receiver, and a float for opening said valve when accumulated foul gas in said auxiliary receiver forces the liquid level below a predetermined level.

3. A refrigerating system including a main receiver for the liquefied refrigerant, an auxiliary receiver, a pipe connection between the lower part of said main receiver and the lower part of said auxiliary receiver for delivering all of the liquid refrigerant to said auxiliary receiver from said main receiver, a main liquid delivery conduit from the lower part of said auxiliary receiver, and a float valve adapted to vent the foul gas from said auxiliary receiver when the liquid therein has been lowered to a predetermined level.

4. A refrigerating apparatus including a main receiver for the liquid refrigerant, an auxiliary receiver, pipe connections from the lower portion of the main receiver to the lower portion of the auxiliary receiver for delivering the liquid from said main receiver to said auxiliary receiver, a main liquid delivery conduit extending from the lower portion of said auxiliary receiver, a foul gas outlet valve connected to the top of the auxiliary receiver, and a float approximately midway of the height of said auxiliary receiver for controlling said valve, whereby the liquid in said auxiliary receiver is maintained in a substantially quiescent state and said valve is opened only when foul gas has accumulated to approximately half the volume of the auxiliary receiver.

5. A refrigerating apparatus including a main receiver for the liquid refrigerant, an auxiliary receiver, pipe connections from the lower portion of the main receiver to the lower portion of the auxiliary receiver for delivering the liquid from said main receiver to said auxiliary receiver, a main liquid delivery conduit leading from said auxiliary receiver at a point closely adjacent to the liquid inlet, and a vent valve connected to the top of the auxiliary receiver.

EDWARD B. McCABE. 

